Evidence for $X(3872)\to J/\psi {\pi }^{+}{\pi }^{-}$ produced in single-tag two-photon interactions

Abstract

We report the first evidence for $X(3872)$ production in two-photon interactions by tagging either the electron or the position in the final state, exploring the highly virtual photon region. The search is performed in $e^{+}{e}^{-}\to e^{+}{e}^{-}J/\psi {\pi }^{+}{\pi }^{-}$, using 825 fb${}^{-1}$ of data collected by the Belle detector operated at the KEKB $e^{+}{e}^{-}$ collider. We observe three $X(3872)$ candidates with an expected background of $0.11\pm 0.10$ events, with a significance of 3.2$\sigma$. We obtain an estimated value for ${\tilde{\Gamma }}_{\gamma \gamma }\mathcal{B}(X(3872)\to J/\psi {\pi }^{+}{\pi }^{-}$) assuming the $Q^2$ dependence predicted by a $c\bar{c}$ meson model, where $-Q^2$ is the invariant mass-squared of the virtual photon. No $X(3915)\to J/\psi {\pi }^{+}{\pi }^{-}$ candidates are found.

arXiv commentTo be published in Physical Review Letters

References in corpus (23)

• A Unified Approach to the Classical Statistical Analysis of Small Signals
• Observation of a narrow charmonium-like state in exclusive B+ -> K+ pi+pi- J/psi decays
• Observation of a New Narrow Charmonium State in Exclusive B+-->K+ pi+pi- J/psi Decays
• Study of $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}J/\psi$ and Observation of a Charged Charmonium-like State at Belle
• Determination of the X(3872) meson quantum numbers
• Measurement of e^+e^- to pi^+pi^-J/psi Cross Section via Initial State Radiation at Belle
• Precise measurement of the $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}J/\psi$ cross section at center-of-mass energies from 3.77 to 4.60 GeV
• Observation of $e^{+}{e}^{-}\to \gamma X(3872)$ at BESIII
• Bounds on the width, mass difference and other properties of X(3872) --> pi+pi-J/psi decays
• Electron Identification in Belle
• Observation of a charmonium-like enhancement in the gamma gamma --> omega J/psi process
• Study of the lineshape of the ${\chi }_{c1}(3872)$ state
• Measurement of the Dipion Mass Spectrum in X(3872) -> J/Psi Pi+ Pi- Decays
• A study of B->X(3872) K, with X(3872)->J/Psi pi+ pi-
• Meson--photon transition form factors and resonance cross-sections in e^+ e^- collisions
• Study of X(3915) --> J/ψω in two-photon collisions
• Study of ${\pi }^0$ pair production in single-tag two-photon collisions
• Observation of psi(3770)--> pi pi J/psi and Measurement of Gamma_{ee}[psi(2S)]
• Study of the ${\psi }_2(3823)$ and ${\chi }_{c1}(3872)$ states in $B^{+}\to \left(J\psi {\pi }^{+}{\pi }^{-}\right)K^{+}$ decays
• Determination of the absolute branching fractions of X(3872) decays
• Radiative decays of the Y(3940), Z(3930) and the X(4160) as dynamically generated resonances
• Search for X(3872) in gamma gamma Fusion and ISR at CLEO
• Study of $K_S^0$ pair production in single-tag two-photon collisions

Cited by in corpus (13)

• Novel approaches in Hadron Spectroscopy
• The study of $\gamma \gamma \to \gamma \psi (2S)$ at Belle
• Two-photon transitions of charmonia on the light front
• The structure of the X(3872) as explained by a Diffusion Monte Carlo calculation
• First Observation of the Direct Production of the ${\chi }_{c1}$ in $e^{+}{e}^{-}$ Annihilation
• Probing the structure of ${\chi }_{c1}(3872)$ with photon transition form factors
• Semileptonic $B_c$ decays to $P-$wave charmonium and the nature of ${\chi }_{c1}(3872)$
• Electroweak production of ${\chi }_{Q1}$ states in $e^{+}{e}^{-}$ collisions: A brief review
• Novel correlated $D^0\overline{D}{}^0$ systems for $c/b$ physics and tests of $T/CPT$
• XYZ spectroscopy at electron-hadron facilities III: Semi-inclusive processes with vector exchanges
• Search for the light hadron decay ${\chi }_{c1}(3872)\to {\pi }^{+}{\pi }^{-}\eta$
• Two-photon physics at future electron-positron colliders
• First measurement of the Q^2 distribution of X(3915) single-tag two-photon production